Beyond Soil Moisture: The Multidimensional Influences of Soil Properties on Leaf Physiological and Biochemical Attributes of Plant Communities Along a Typical Arid Coast of Hainan, China

Drought, a complex environmental stressor, exerts a multifaceted impact on plants through soil water deficit and associated alterations in soil other physicochemical properties. This study aimed to quantitative assessment of the relative influence of soil water content (SWC) and other soil physicochemical properties on the physiological and biochemical attributes of plant communities in arid habitats. Along the arid coast of Qizi Bay, Changjiang County, Hainan, China, we established four zones to systematically collect leaf and soil samples from plant communities. Variability in the leaf physiological and biochemical traits of plant communities across these zones and their quantitative associations to soil physicochemical properties were explored. SWC showed no significant differences among sampling zones, with all average values being below 26%. Except for pH and sand proportion, other soil physicochemical properties are significantly higher in E'ling than in other zones. Most leaf physiological and biochemical characteristics of plant communities also showed no significant differences among sampling zones. Redundancy (hierarchical partitioning) and structural equation modeling indicated: in addition to SWC, other soil physicochemical properties (such as soil ammonium nitrogen content, silt proportion, total phosphorus content, and clay proportion) also exerted a non-negligible role in determining the leaf physiological and biochemical characteristics of plant communities in Qizi Bay. In arid coastal soils, other soil physicochemical properties, beyond SWC, exert a significant influence on the leaf physiological and biochemical characteristics of plant communities. A comprehensive strategy, not limited to irrigation, is essential for restoration and sustainability of vegetation in arid coasts.